Kenyan runner Wesley Korir, winner of the 2012 Boston Marathon, tells CNN that being a runner is “like a volunteer job” for Kenyans. Now, due to a new tax on athletes’ prize money from international competitions, Kenya’s top athletes may begin competing under different nationalities in protest.

The plan from the Kenyan Revenue Authority (KRA) makes athletes’ winnings abroad taxable income under domestic law, which means that prize-winning athletes could be paying 30% of their earnings from competitions. With deductions including taxes to the host country and percentages set aside for agents and managers, Korir says winners are left with only 15% of the prize money.

Another issue with the tax, Korir says, is that unlike teachers and other workers, athletes receive no government funding.

“They have a lot of options, but they have chosen to stay in this country, you know, because they love their country,” he says. “But now, if their country doesn’t love them, they don’t have an option.”

Don't many, if not most countries tax foreign earnings to some degree? This is a problem common to professional athletes in international sports and is why it's common to do country shopping, i.e., to set up residence in more favorable tax situations.